udp_usrreq.c revision 1.13
1 /* 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * from: @(#)udp_usrreq.c 8.4 (Berkeley) 1/21/94 34 * $Id: udp_usrreq.c,v 1.13 1994/05/13 06:06:56 mycroft Exp $ 35 */ 36 37 #include <sys/param.h> 38 #include <sys/malloc.h> 39 #include <sys/mbuf.h> 40 #include <sys/protosw.h> 41 #include <sys/socket.h> 42 #include <sys/socketvar.h> 43 #include <sys/errno.h> 44 #include <sys/stat.h> 45 46 #include <net/if.h> 47 #include <net/route.h> 48 49 #include <netinet/in.h> 50 #include <netinet/in_systm.h> 51 #include <netinet/ip.h> 52 #include <netinet/in_pcb.h> 53 #include <netinet/ip_var.h> 54 #include <netinet/ip_icmp.h> 55 #include <netinet/udp.h> 56 #include <netinet/udp_var.h> 57 58 /* 59 * UDP protocol implementation. 60 * Per RFC 768, August, 1980. 61 */ 62 #ifndef COMPAT_42 63 int udpcksum = 1; 64 #else 65 int udpcksum = 0; /* XXX */ 66 #endif 67 68 struct sockaddr_in udp_in = { sizeof(udp_in), AF_INET }; 69 struct inpcb *udp_last_inpcb = &udb; 70 71 static void udp_detach __P((struct inpcb *)); 72 static void udp_notify __P((struct inpcb *, int)); 73 static struct mbuf *udp_saveopt __P((caddr_t, int, int)); 74 75 void 76 udp_init() 77 { 78 udb.inp_next = udb.inp_prev = &udb; 79 } 80 81 void 82 udp_input(m, iphlen) 83 register struct mbuf *m; 84 int iphlen; 85 { 86 register struct ip *ip; 87 register struct udphdr *uh; 88 register struct inpcb *inp; 89 struct mbuf *opts = 0; 90 int len; 91 struct ip save_ip; 92 93 udpstat.udps_ipackets++; 94 95 /* 96 * Strip IP options, if any; should skip this, 97 * make available to user, and use on returned packets, 98 * but we don't yet have a way to check the checksum 99 * with options still present. 100 */ 101 if (iphlen > sizeof (struct ip)) { 102 ip_stripoptions(m, (struct mbuf *)0); 103 iphlen = sizeof(struct ip); 104 } 105 106 /* 107 * Get IP and UDP header together in first mbuf. 108 */ 109 ip = mtod(m, struct ip *); 110 if (m->m_len < iphlen + sizeof(struct udphdr)) { 111 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 112 udpstat.udps_hdrops++; 113 return; 114 } 115 ip = mtod(m, struct ip *); 116 } 117 uh = (struct udphdr *)((caddr_t)ip + iphlen); 118 119 /* 120 * Make mbuf data length reflect UDP length. 121 * If not enough data to reflect UDP length, drop. 122 */ 123 len = ntohs((u_short)uh->uh_ulen); 124 if (ip->ip_len != len) { 125 if (len > ip->ip_len) { 126 udpstat.udps_badlen++; 127 goto bad; 128 } 129 m_adj(m, len - ip->ip_len); 130 /* ip->ip_len = len; */ 131 } 132 /* 133 * Save a copy of the IP header in case we want restore it 134 * for sending an ICMP error message in response. 135 */ 136 save_ip = *ip; 137 138 /* 139 * Checksum extended UDP header and data. 140 */ 141 if (udpcksum && uh->uh_sum) { 142 ((struct ipovly *)ip)->ih_next = 0; 143 ((struct ipovly *)ip)->ih_prev = 0; 144 ((struct ipovly *)ip)->ih_x1 = 0; 145 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 146 if (uh->uh_sum = in_cksum(m, len + sizeof (struct ip))) { 147 udpstat.udps_badsum++; 148 m_freem(m); 149 return; 150 } 151 } 152 153 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 154 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 155 struct socket *last; 156 /* 157 * Deliver a multicast or broadcast datagram to *all* sockets 158 * for which the local and remote addresses and ports match 159 * those of the incoming datagram. This allows more than 160 * one process to receive multi/broadcasts on the same port. 161 * (This really ought to be done for unicast datagrams as 162 * well, but that would cause problems with existing 163 * applications that open both address-specific sockets and 164 * a wildcard socket listening to the same port -- they would 165 * end up receiving duplicates of every unicast datagram. 166 * Those applications open the multiple sockets to overcome an 167 * inadequacy of the UDP socket interface, but for backwards 168 * compatibility we avoid the problem here rather than 169 * fixing the interface. Maybe 4.5BSD will remedy this?) 170 */ 171 172 /* 173 * Construct sockaddr format source address. 174 */ 175 udp_in.sin_port = uh->uh_sport; 176 udp_in.sin_addr = ip->ip_src; 177 m->m_len -= sizeof (struct udpiphdr); 178 m->m_data += sizeof (struct udpiphdr); 179 /* 180 * Locate pcb(s) for datagram. 181 * (Algorithm copied from raw_intr().) 182 */ 183 last = NULL; 184 for (inp = udb.inp_next; inp != &udb; inp = inp->inp_next) { 185 if (inp->inp_lport != uh->uh_dport) 186 continue; 187 if (inp->inp_laddr.s_addr != INADDR_ANY) { 188 if (inp->inp_laddr.s_addr != 189 ip->ip_dst.s_addr) 190 continue; 191 } 192 if (inp->inp_faddr.s_addr != INADDR_ANY) { 193 if (inp->inp_faddr.s_addr != 194 ip->ip_src.s_addr || 195 inp->inp_fport != uh->uh_sport) 196 continue; 197 } 198 199 if (last != NULL) { 200 struct mbuf *n; 201 202 if ((n = m_copy(m, 0, M_COPYALL)) != NULL) { 203 if (sbappendaddr(&last->so_rcv, 204 (struct sockaddr *)&udp_in, 205 n, (struct mbuf *)0) == 0) { 206 m_freem(n); 207 udpstat.udps_fullsock++; 208 } else 209 sorwakeup(last); 210 } 211 } 212 last = inp->inp_socket; 213 /* 214 * Don't look for additional matches if this one does 215 * not have either the SO_REUSEPORT or SO_REUSEADDR 216 * socket options set. This heuristic avoids searching 217 * through all pcbs in the common case of a non-shared 218 * port. It * assumes that an application will never 219 * clear these options after setting them. 220 */ 221 if ((last->so_options&(SO_REUSEPORT|SO_REUSEADDR) == 0)) 222 break; 223 } 224 225 if (last == NULL) { 226 /* 227 * No matching pcb found; discard datagram. 228 * (No need to send an ICMP Port Unreachable 229 * for a broadcast or multicast datgram.) 230 */ 231 udpstat.udps_noportbcast++; 232 goto bad; 233 } 234 if (sbappendaddr(&last->so_rcv, (struct sockaddr *)&udp_in, 235 m, (struct mbuf *)0) == 0) { 236 udpstat.udps_fullsock++; 237 goto bad; 238 } 239 sorwakeup(last); 240 return; 241 } 242 /* 243 * Locate pcb for datagram. 244 */ 245 inp = udp_last_inpcb; 246 if (inp->inp_lport != uh->uh_dport || 247 inp->inp_fport != uh->uh_sport || 248 inp->inp_faddr.s_addr != ip->ip_src.s_addr || 249 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) { 250 inp = in_pcblookup(&udb, ip->ip_src, uh->uh_sport, 251 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD); 252 if (inp) 253 udp_last_inpcb = inp; 254 udpstat.udpps_pcbcachemiss++; 255 } 256 if (inp == 0) { 257 udpstat.udps_noport++; 258 if (m->m_flags & (M_BCAST | M_MCAST)) { 259 udpstat.udps_noportbcast++; 260 goto bad; 261 } 262 *ip = save_ip; 263 ip->ip_len += iphlen; 264 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 265 return; 266 } 267 268 /* 269 * Construct sockaddr format source address. 270 * Stuff source address and datagram in user buffer. 271 */ 272 udp_in.sin_port = uh->uh_sport; 273 udp_in.sin_addr = ip->ip_src; 274 if (inp->inp_flags & INP_CONTROLOPTS) { 275 struct mbuf **mp = &opts; 276 277 if (inp->inp_flags & INP_RECVDSTADDR) { 278 *mp = udp_saveopt((caddr_t) &ip->ip_dst, 279 sizeof(struct in_addr), IP_RECVDSTADDR); 280 if (*mp) 281 mp = &(*mp)->m_next; 282 } 283 #ifdef notyet 284 /* options were tossed above */ 285 if (inp->inp_flags & INP_RECVOPTS) { 286 *mp = udp_saveopt((caddr_t) opts_deleted_above, 287 sizeof(struct in_addr), IP_RECVOPTS); 288 if (*mp) 289 mp = &(*mp)->m_next; 290 } 291 /* ip_srcroute doesn't do what we want here, need to fix */ 292 if (inp->inp_flags & INP_RECVRETOPTS) { 293 *mp = udp_saveopt((caddr_t) ip_srcroute(), 294 sizeof(struct in_addr), IP_RECVRETOPTS); 295 if (*mp) 296 mp = &(*mp)->m_next; 297 } 298 #endif 299 } 300 iphlen += sizeof(struct udphdr); 301 m->m_len -= iphlen; 302 m->m_pkthdr.len -= iphlen; 303 m->m_data += iphlen; 304 if (sbappendaddr(&inp->inp_socket->so_rcv, (struct sockaddr *)&udp_in, 305 m, opts) == 0) { 306 udpstat.udps_fullsock++; 307 goto bad; 308 } 309 sorwakeup(inp->inp_socket); 310 return; 311 bad: 312 m_freem(m); 313 if (opts) 314 m_freem(opts); 315 } 316 317 /* 318 * Create a "control" mbuf containing the specified data 319 * with the specified type for presentation with a datagram. 320 */ 321 struct mbuf * 322 udp_saveopt(p, size, type) 323 caddr_t p; 324 register int size; 325 int type; 326 { 327 register struct cmsghdr *cp; 328 struct mbuf *m; 329 330 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 331 return ((struct mbuf *) NULL); 332 cp = (struct cmsghdr *) mtod(m, struct cmsghdr *); 333 bcopy(p, CMSG_DATA(cp), size); 334 size += sizeof(*cp); 335 m->m_len = size; 336 cp->cmsg_len = size; 337 cp->cmsg_level = IPPROTO_IP; 338 cp->cmsg_type = type; 339 return (m); 340 } 341 342 /* 343 * Notify a udp user of an asynchronous error; 344 * just wake up so that he can collect error status. 345 */ 346 static void 347 udp_notify(inp, errno) 348 register struct inpcb *inp; 349 int errno; 350 { 351 inp->inp_socket->so_error = errno; 352 sorwakeup(inp->inp_socket); 353 sowwakeup(inp->inp_socket); 354 } 355 356 void 357 udp_ctlinput(cmd, sa, ip) 358 int cmd; 359 struct sockaddr *sa; 360 register struct ip *ip; 361 { 362 register struct udphdr *uh; 363 extern struct in_addr zeroin_addr; 364 extern u_char inetctlerrmap[]; 365 366 if (!PRC_IS_REDIRECT(cmd) && 367 ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)) 368 return; 369 if (ip) { 370 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 371 in_pcbnotify(&udb, sa, uh->uh_dport, ip->ip_src, uh->uh_sport, 372 cmd, udp_notify); 373 } else 374 in_pcbnotify(&udb, sa, 0, zeroin_addr, 0, cmd, udp_notify); 375 } 376 377 int 378 udp_output(inp, m, addr, control) 379 register struct inpcb *inp; 380 register struct mbuf *m; 381 struct mbuf *addr, *control; 382 { 383 register struct udpiphdr *ui; 384 register int len = m->m_pkthdr.len; 385 struct in_addr laddr; 386 int s, error = 0; 387 388 if (control) 389 m_freem(control); /* XXX */ 390 391 if (addr) { 392 laddr = inp->inp_laddr; 393 if (inp->inp_faddr.s_addr != INADDR_ANY) { 394 error = EISCONN; 395 goto release; 396 } 397 /* 398 * Must block input while temporarily connected. 399 */ 400 s = splnet(); 401 error = in_pcbconnect(inp, addr); 402 if (error) { 403 splx(s); 404 goto release; 405 } 406 } else { 407 if (inp->inp_faddr.s_addr == INADDR_ANY) { 408 error = ENOTCONN; 409 goto release; 410 } 411 } 412 /* 413 * Calculate data length and get a mbuf 414 * for UDP and IP headers. 415 */ 416 M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT); 417 if (m == 0) { 418 error = ENOBUFS; 419 goto release; 420 } 421 422 /* 423 * Fill in mbuf with extended UDP header 424 * and addresses and length put into network format. 425 */ 426 ui = mtod(m, struct udpiphdr *); 427 ui->ui_next = ui->ui_prev = 0; 428 ui->ui_x1 = 0; 429 ui->ui_pr = IPPROTO_UDP; 430 ui->ui_len = htons((u_short)len + sizeof (struct udphdr)); 431 ui->ui_src = inp->inp_laddr; 432 ui->ui_dst = inp->inp_faddr; 433 ui->ui_sport = inp->inp_lport; 434 ui->ui_dport = inp->inp_fport; 435 ui->ui_ulen = ui->ui_len; 436 437 /* 438 * Stuff checksum and output datagram. 439 */ 440 ui->ui_sum = 0; 441 if (udpcksum) { 442 if ((ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len)) == 0) 443 ui->ui_sum = 0xffff; 444 } 445 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 446 ((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl; /* XXX */ 447 ((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos; /* XXX */ 448 udpstat.udps_opackets++; 449 error = ip_output(m, inp->inp_options, &inp->inp_route, 450 inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST), 451 inp->inp_moptions); 452 453 if (addr) { 454 in_pcbdisconnect(inp); 455 inp->inp_laddr = laddr; 456 splx(s); 457 } 458 return (error); 459 460 release: 461 m_freem(m); 462 return (error); 463 } 464 465 u_long udp_sendspace = 9216; /* really max datagram size */ 466 u_long udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in)); 467 /* 40 1K datagrams */ 468 469 /*ARGSUSED*/ 470 int 471 udp_usrreq(so, req, m, addr, control) 472 struct socket *so; 473 int req; 474 struct mbuf *m, *addr, *control; 475 { 476 struct inpcb *inp = sotoinpcb(so); 477 int error = 0; 478 int s; 479 480 if (req == PRU_CONTROL) 481 return (in_control(so, (int)m, (caddr_t)addr, 482 (struct ifnet *)control)); 483 if (inp == NULL && req != PRU_ATTACH) { 484 error = EINVAL; 485 goto release; 486 } 487 /* 488 * Note: need to block udp_input while changing 489 * the udp pcb queue and/or pcb addresses. 490 */ 491 switch (req) { 492 493 case PRU_ATTACH: 494 if (inp != NULL) { 495 error = EINVAL; 496 break; 497 } 498 s = splnet(); 499 error = in_pcballoc(so, &udb); 500 splx(s); 501 if (error) 502 break; 503 error = soreserve(so, udp_sendspace, udp_recvspace); 504 if (error) 505 break; 506 ((struct inpcb *) so->so_pcb)->inp_ip.ip_ttl = ip_defttl; 507 break; 508 509 case PRU_DETACH: 510 udp_detach(inp); 511 break; 512 513 case PRU_BIND: 514 s = splnet(); 515 error = in_pcbbind(inp, addr); 516 splx(s); 517 break; 518 519 case PRU_LISTEN: 520 error = EOPNOTSUPP; 521 break; 522 523 case PRU_CONNECT: 524 if (inp->inp_faddr.s_addr != INADDR_ANY) { 525 error = EISCONN; 526 break; 527 } 528 s = splnet(); 529 error = in_pcbconnect(inp, addr); 530 splx(s); 531 if (error == 0) 532 soisconnected(so); 533 break; 534 535 case PRU_CONNECT2: 536 error = EOPNOTSUPP; 537 break; 538 539 case PRU_ACCEPT: 540 error = EOPNOTSUPP; 541 break; 542 543 case PRU_DISCONNECT: 544 if (inp->inp_faddr.s_addr == INADDR_ANY) { 545 error = ENOTCONN; 546 break; 547 } 548 s = splnet(); 549 in_pcbdisconnect(inp); 550 inp->inp_laddr.s_addr = INADDR_ANY; 551 splx(s); 552 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 553 break; 554 555 case PRU_SHUTDOWN: 556 socantsendmore(so); 557 break; 558 559 case PRU_SEND: 560 return (udp_output(inp, m, addr, control)); 561 562 case PRU_ABORT: 563 soisdisconnected(so); 564 udp_detach(inp); 565 break; 566 567 case PRU_SOCKADDR: 568 in_setsockaddr(inp, addr); 569 break; 570 571 case PRU_PEERADDR: 572 in_setpeeraddr(inp, addr); 573 break; 574 575 case PRU_SENSE: 576 /* 577 * stat: don't bother with a blocksize. 578 */ 579 return (0); 580 581 case PRU_SENDOOB: 582 case PRU_FASTTIMO: 583 case PRU_SLOWTIMO: 584 case PRU_PROTORCV: 585 case PRU_PROTOSEND: 586 error = EOPNOTSUPP; 587 break; 588 589 case PRU_RCVD: 590 case PRU_RCVOOB: 591 return (EOPNOTSUPP); /* do not free mbuf's */ 592 593 default: 594 panic("udp_usrreq"); 595 } 596 597 release: 598 if (control) { 599 printf("udp control data unexpectedly retained\n"); 600 m_freem(control); 601 } 602 if (m) 603 m_freem(m); 604 return (error); 605 } 606 607 static void 608 udp_detach(inp) 609 struct inpcb *inp; 610 { 611 int s = splnet(); 612 613 if (inp == udp_last_inpcb) 614 udp_last_inpcb = &udb; 615 in_pcbdetach(inp); 616 splx(s); 617 } 618 619 /* 620 * Sysctl for udp variables. 621 */ 622 udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 623 int *name; 624 u_int namelen; 625 void *oldp; 626 size_t *oldlenp; 627 void *newp; 628 size_t newlen; 629 { 630 /* All sysctl names at this level are terminal. */ 631 if (namelen != 1) 632 return (ENOTDIR); 633 634 switch (name[0]) { 635 case UDPCTL_CHECKSUM: 636 return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum)); 637 default: 638 return (ENOPROTOOPT); 639 } 640 /* NOTREACHED */ 641 } 642
Indexes created Tue Sep 23 14:10:03 GMT 2025